https://issues.dlang.org/show_bug.cgi?id=21070

          Issue ID: 21070
           Summary: -profile=gc makes the program much slower
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: tim.dlang@t-online.de

When compiling a program with -profile=gc it becomes much slower.
GC.stats is called for every allocation,
but it collects more information, than is needed for
-profile=gc. Replacing the call to GC.stats with a new function,
which only returns the needed information, makes the program fast again.

I will create a pull request later.

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